Lethal and sublethal effects of diluted bitumen and conventional oil on fathead minnow (Pimephales promelas) larvae exposed during their early development

The effects of dissolved petroleum hydrocarbons on benthic organisms: Chironomids and amphipods

“…PACs with 2-and 3aromatic rings were the most prevalent PAHs and alkylated PAHs in the WAFs of the diluted bitumens, especially the Bluesky one. The chemical profiles of the diluted bitumen in our study thus showed a profile of PAHs similar to other studies on this type of oil, such as Lara-Jacobo et al ( 2021), Berube et al (2021), andSchiano Di Lombo et al (2021). Naphthalene and its alkyl derivatives were the compounds most present in the WAFs of both our study and Schiano Di Lombo et al (2021).…”

“…This syndrome brings together several symptoms such as craniofacial deformation, yolk sac, and pericardial edema, fin erosion and spinal curvatures, which, of course, cannot be observed in invertebrates. More specifically, the study by Berube et al (2021) showed that diluted bitumens could be more toxic than conventional oils to Pimephales promelas larvae, which is also demonstrated in our study for C. riparius. The most toxic oil was found to be Clearwater McMurray diluted bitumen, while the Bluesky diluted bitumen and the conventional heavy oil (Lloydminster) were equally toxic.…”

“…To our knowledge, no other studies have investigated the effects of diluted bitumen WAFs on the size of invertebrates. In fish, exposures of Pimephales promelas larvae to various diluted bitumens (Clearwater McMurray, Bluesky) did not either lead to any significant effect on organism weights (2597-3508 µg/L VOC/B-TEX, 100 g/L WAF; 60.67-22.05 µg/L TPAC, 100 g/L WAF) (Lara-Jacobo et al, 2021;Berube et al, 2021). In contrast, Berube et al (2021) demonstrated a decrease in the weight of P. promelas larvae exposed to a conventional heavy oil, Lloydminster (789 µg/L VOC/B-TEX, WAF 100 g/L; 89.66 µg/L TPAC, WAF 100 g/L) but not to the diluted bitumens.…”

“…Everitt et al (2020) when exposing the epibenthic amphipod Hyalella azteca to a water-soluble fraction (WSF, similar to WAF but excluding droplets or particulate oil) of a weathered diluted bitumen containing 1.08 μg/L total PAHs did not observe lethality. Overall, few studies have compared the toxicity of dissolved compounds in diluted bitumen with conventional oil to aquatic organisms (Berube et al, 2021;Lara-Jacobo et al, 2021) and, to our knowledge, there are none on benthic invertebrates. Most current literature on the toxicity of diluted bitumen on aquatic species is on fish (Wallace et al, 2020).…”

“…Most current literature on the toxicity of diluted bitumen on aquatic species is on fish (Wallace et al, 2020). The most recent studies have shown that diluted bitumen induce embryotoxicity, deformities, cardiotoxicity, DNA damage, and impaired reproduction in fish (Berube et al, 2021;Dew et al, 2015;Lara-Jacobo et al, 2021;Madison et al, 2017;NAS, 2016;Wallace et al, 2020).…”